smithy
Active member
Anyone know how I can test the masthead unit, five wire Clipper type. The mast is down at the moment.
Nasa Masthead Wind Unit
- Thread starter smithy
- Start date
Graham_Wright
Well-known member
Connect it to the display. (But don't let the wires short to each other - don't ask!).
neil_s
Well-known member
As above - I have a short adapter cable for this very purpose. Easily made - the plugs are simple 5 pin DIN's.
smithy
Active member
The display wasn't showing anything at all before I took tke mast down, I'm trying to work out whether its the display or the mast head unit thats at fault. Should the display show anything if it's not attached to the head unit? Display is getting power.
neil_s
Well-known member
I can't remember, offhand - but will be at the boat next Tuesday and can do any checks you need, then. My mast is down, but can connect up M/H unit as above! Bear in mind that a meter might register voltage at the unit, but a poor connection down the line a ways will stop the unit powering up - had this problem last season.
StefanSG
Active member
Think you need to connect to head unit to test
Screen is negative - use for neg probe
Red is power supply and should show 5v
Black varies between 1v and 4v
Blue varies between 1v and 4v
White pulses, but you won't be able to read anything on a meter
Do you have the small black interface box that hangs off the back of the head unit, where the cables patch together on a small PCB ? Open that up and make sure theres no corrosion
(copied and pasted from the archives here, but helped me to troubleshoot mine)
Screen is negative - use for neg probe
Red is power supply and should show 5v
Black varies between 1v and 4v
Blue varies between 1v and 4v
White pulses, but you won't be able to read anything on a meter
Do you have the small black interface box that hangs off the back of the head unit, where the cables patch together on a small PCB ? Open that up and make sure theres no corrosion
(copied and pasted from the archives here, but helped me to troubleshoot mine)
Last edited:
Rappey
Well-known member
As in blank or it has a display but not showing a reading ?
KompetentKrew
Well-known member
NASA have incredibly good customer service - they will be able to answer your questions. They respond to email within a day or two.
smithy
Active member
Blank
Rappey
Well-known member
After posting ive discovered my nasa only has 3 wires so not much help.
KompetentKrew has a great idea.
KompetentKrew has a great idea.
smithy
Active member
Just an update, the NASA display units do activate when not wired to mast head unit. Thanks to Neil_S tip about the din cable you can quickly rule out the mast cable. I ended sending the whole unit back to NASA, they replaced the some of the components on the PCB , the shaft and magnet in the masthead unit. They charged reasonable £35 including the postage with a two day turn around.
